Improvement in head-blocks for saw-mills



y `Be it known that I, GEORGE ministerie aient chimie.

GEORGEJSELDEN, or ERIE, PENNSYLVANIA.

.` Lentement.Nu-107,728, dated september 27', 1870.

y IMPROVEMENT iN 'HEAD-BLocKs Fon sAw-wnLLs.4

The Schedule referred toir'rthese Letters Patent andina'king part of the same 'To all 'whom traag/"concern SELDEN, fot' Erie, county of vErie -and State of Pennsylvania, have inventeda new and improved Pawl and Ratchet lDevice' for Head-Blockalof which' the following is a full, clear,

and'exact,descriptiomreference'being-had to the ac-4 companying drawing making a part of this specification, in which- Figure 1 is a plan oi-.top view of the device; Y

- Figure 2 isa. side view of the same, showing the' partsin proper position for advancing the `log to the saw; i

' Figure 3 is a side -view lrepresenting the partsin position-for withdrawingthe log or head-block from the saw; and i g Figure vall. isa transverse vertical sectional view 'through lineas y, fig. v1.

This Vinvention consists iu au improvement upon a head-block ratchet patented by me, June 7, .18'10, in

which two shipping-leverswere employed, 4both of which were required to be used in eiiecting'any change in the direction ih which the headhloclcwas to be moved, while, in my improved construction, the change is eected by a Asingle movement of a single lever, and the partsl are so constructedand arrangedthat the throw of this lever in either direction islimited to about the required distance, and, when it has been moved to the proper position, itis then locked automatically, so as to avoid'4 accidental displacement, as

' will befullyexplained. in the following descriptioniof its construction;

f In thedrawing A represents a base plate, or the side of a headblock, and Ai a heut arm ori' bracket, firmly secured to plate A, substantially in the relation shown in tig. 1, these two pieces' forming `a support, upon which the working parts of `the device are mounted.

B' is a ratcheted wheel, shown in full lines in figs. 1 and 4,.and in dotted lines in figs. 2 and 3. This wheel is provided with hubs or sleeves b b', and, in practice,- is keyed Vto shaft B', which represents the pinion-shaft, said shaft having suitable bearings in plate 'A and Vbracket A'. l

.O is the main opeiating lever, forked'at one end, as

, shown .in g. '1. Each arm of this lever is expanded at its lower end, and lencircles or incloses the hubs or sleeves of ratchet-wheel B,i n such manner'astooscillatejabout shaft B' as a center. Arm c of lever 0 ts closely hub b, but the perforation or bearing iu armo1 is larger 4than the outside diameter of hub b', to whichl i't is concentric, thereby admitting of the iuterposition of another sleeve, d, of the double cam H, which will be hereinafter described. '0.l is a pawl located between the arms of lever '0, in such position that it 'can he 'made to engage-with ratohetewheel B, and vibrate about pivot c". This pawl is shown in dotted lines in iig. 3, and partly in dotted and partly in full lines, fig. 2.

021s a tongue-spring, attached at one end to the under side of lever Q, the free end of said spring engaging with the upper side of a heel extension of pawl .01, as'shown in dotted lines at c2, figs. 2 and 3.

D' -D' isa-series of pawls -pivoted in lever O.

E E is another series of pawls, arranged upon the opposite Aside of 1 the wheel, to check its return from the point to which it has been advanced by pawls D' DI As the dil'erencein the length of these pawls, and the manner in which theyare arranged, so that the different membersiof the same group act successively upon the wheel, is fully explained inthe patenthefore referred to, I will notent'er into the detailshere.

' F is a'tripping-shaft, provided'with a. lip or jaw, f, t

by means of which the pawls E E are withdrawn'from wheel-Bzwhen require Shaft F is actuated by arm ll", on'thel front o" outer side of supporting-arm AC VThe throw of arrn F' is limited by twp stops, jf1, uponarm AQ i vGf is a pivot-stop, which engages with an adj ustabe stop supported from plate A, or its equivalent, but

not shown, foifiegulating the extent of the throw of lever G in its forward movement. Arm A is expanded or `enlarged upon its inner end,

that is, th'c end toward lever O, iu such manner as tov form a rib or stop concentric with shaft B', and terminating at each end in shoulders a a', shown-plainly in iigs. 2 and 3.

,H is a double cam-plate, employed for throwing the parts into and ont of action. This cam is essentially and in its operation the equivalent of twocams, each of which operates in its turn upon a dili'erent pawl or set of pawls, and I will,therefore, proceed to describe them, and to indicate their-functions separately. One

of them, which I will designate as theI inner one, b.-

ployed to actuate. the set of pawls D' D', which are made ,wider than the face of `wheel B, so as to overlap and rest upon the vperiphery of said inner cam, as shown at g.1.- .This cam is mountedgipon hub b' of wheel B, and is-of suoli size `that, when placed with i-ts greatest radius next to pawls D', said pawls will be lifted from wheel B, as in fig. 3, but when the position of the cam is reversed the pawls shall be free to engage'with wheel B, as in figs. 1 and 2. The outer cam is used to control the movements of spring pawl G, whichis wide enough to overlap-.wheel B and both canis,-but is noteiiected by the inner one, becausethere is. av notch cut in the lower end of the pawl, att 'a point opposite said inner cam, and into which the cam can enter `leaving aspnr upon lthe outer side of the pawl, which rest-s upon the outer cam.

These cams are, however, made by preference in one piece, and. are provided with 'a sleeve, h, which occupies the space above referred to, between sleeve b' and arm c ot' lever O, and of sufficient length to reach a short distance beyond arm A', tig. 4.

I is a shipping-lever, expanded lat one end into a ring of sutcient size to encircle sleeve h, to which it is rigidly fastened by the key i. A portion of the outer face of this ring is cut away, leaving a section of it of smaller outside diameter, and thereby forming two shoulders, il i?, shown in figs. 2 and 3.

I' is a spring-latch, pivoted to shipping-lever I, and serving to lock the devices in proper position, as will presently be explained.

In figs. 1 and 2 the parts are represent-ed as being ir proper position for feeding the` log to thesaw. It will be seen, by reference to lig. 2, that pawls D' and E are engaged with wheel B, so that an upward movement of lever O will carry the wheel with it, and pawls E retain said wheel as the lever is returned.

P, and it will also be seen that latch I', engaging with shoulder a', on armA', prevents an upward movement of shippinglever I.

In order to withdraw the log or head-blockfrom the saw, I release spring-latch I' from shoulder a', and move the shipping-lever over iut-o the position shown in fig. 3, carrying with it' the double cam H. In this figure,-it will he seen, the position ofthe two cams is exactly the reverse of what it is in iig. 2, that is, the v inner one is now above the arm, with pawls D' resting upon it, so that they cannot engage with wheelB, while the outer camels thrown below arm A', so that spring pawl Cl, traveling over the lesser radius of said cam, may engage with wheel B, moving it only at the downward stroke of lever C, the pawls E being withdrawn by lip fl, on shaft F, to permit this retrograde movement. This change in the position of shaft F is effected by shoulder t2 striking against the outer end of arm F', forcing it down to stop f.

It will be readily seen that arm F and stops f fl serve -to limit the throw of shipping-lever I, and, also, that when the parts are in either of the working relations above described, the combination of shippinglever I, spring-latch 1', and arm F, with stop f and shoulder a, or with stop f l and shoulder a', form a. p erfect lock, to guard against accidental displacement.

Having now described my invention,

\Vhat I claim as new,- and desire to secure by Letters Patent, is-

'1. The combination of the operating lever C, the ratcheted wheel B, the pawls (ll D', double cam H, and shipping-lever I, constructed and operating substantially as set forth.

2. Ihe lever I, provided with shoulders i" i2, in combination with arm F and tripping-shaft F.

3. The lever I, provided with shoulders i t2, in combination with tripping-shaft F, arm F', latch l', and arm A', provided with shoulders a u' and stops f f l, for locking the tlipping-shaft, substantially as set forth.

4. 'lhe combination of lever I, latch I', arm A', provided with shoulders a a and studsv f f, the arm F', and cam H, for locking the cam, as set forth.

GEO. SELDEN.

Witnesses:

W. L. CLEVELAND,

F. CLEVELAND. 

